Anti-induction telephone system.



- 'PATENTED SEPT. l, 1903 W. GONDON &: A. BARRETT.

ANTI-INDUCTION TELEPHONE SYSTEM.

APPLICATION FILED MAR. 24, 1902.

so MODEL.

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iatented September 1,

PATENT OFFICE.

IVILLIAM CONDON AND ALBERT BARRETT, OF KANSAS CITY, MISSOURI.

ANTI-INDUCTION TELEPHONE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 737,711, datedSeptember 1, 1903.

Application filed March 24, 1902. Serial No. 99,574. (No model.)

To all whom it may concern:

Be it known that we, WILLIAM CONDON and ALBERT BARRETT, citizens of theUnited States, residing in Kansas City, county of Jackson, and State ofMissouri, have invented a new and useful Improvement in Anti-InductionTelephone Systems, of which the following is a specification, referencebeing had therein to the accompanying drawings, forming a part thereof.

Our invention relates to improvements in telephony.

The object of our invention is to provide means for preventing in thereceiving-telephone disturbing sounds due to the inductive action ofother than the telephonic currents.

Our invention provides atransmittingcircuit with means for causingtelephonic currents to traverse the same, a secondary circuit operatedby ind nation from the transmitting-circuit, a telephone-receiver in thesaid secondary or receiving circuit, and means for varying the inductiveefficiency between the two circuit-s.

Our invention provides, further, means for varying oppositely thestrength of the telephonic currents, thus compensating for the variationin inductive efficiency between the two circuits.

Our invention provides, further, means by which the variation ofinductive efficiency and the variation of the strength of the telephoniccurrents may be simultaneously accomplished.

Ouriuvention provides, further, means for varying the efficiency betweenthe transmitting and receiving circuits by cutting in or cutting outfrom inductive action portions of one of said circuits.

Our invention provides, further, means for varying the inductiveefficiency between the transmitting and the receiving circuits,consisting in cutting in or cutting out from inductive action portionsof one of the windings of an induction device, consisting of twoelements inductively related to each other, one element thereof beingdisposed in the transmitting and the other element in the receivingcircuit.

Ourinvention provides,still further,atransmitting-circuit, means forcausing telephonic currents to traverse the same, a plurality ofsecondary circuits, a telephonereceiver in each of said secondarycircuits, and means for varying the inductive efficiency between theprimary and the secondary circuits.

Other features of novelty are hereinafter fully described and claimed.

In the accompanying drawings we have shown various means for carryingourinvention into efiect.

In practicing our invention we prefer to place the transmitters andbattery or other source of electrical generation in series in the lineor transmitting circuit. The receiving-telephones are placed insecondary circuits operated by induction from the transmitting-circuit.In the event that stray currents get upon the transmittingcircuit byinduction or by any other manner our invention provides for thedecreasing of the inductive efficiency between the transmitting and thereceiving circuits until the disturbances in the receiving-telephonesare eliminated and compensating for the weakened effect of thetelephonic currents upon the receivers by increasing the strength of thetelephonic currents.

Referringto the drawings, Figure 1 is a diagrammatic view of a telephonesystem embodying the features of our invention in which the inductiveefficiency is varied by movement of a portion of one circuit in theinductive field of the other circuit. Fig. 2 is a similar view showing amodification of our system in which the inductive efficiency is variedby cutting in or out from inductive action certain portions of thetransmitting-cm cuit. Fig. 3 is a view similar to Fig. 1 of one end ofthe transmitting-circuit, showing another modification in which theinductive efliciency is varied by cutting in or out of inductive actioncertain portions of the receivingcircuit. Fig. 4 isa view of stillanother modification in which the inductive efficiency is varied bychanging the position relative to the two circuits of a reinforcingagent, such as an iron core of an induction-coil. In Figs. 1, 2, and ameans are shown by which the variation of the strength of the telephoniccurrents and the variation of the inductive effi: ciency is accomplishedsimultaneously.

Similar characters of reference indicate similar parts.

1 and 4 indicate two stations connected by the two linetransmitting-wires 2 and 3.

5 indicates a wire carrying currents from which are induced straycurrents traversing the wires 2 and 3.

6 indicates the primary wire of an induction-coil located one at eachstation, and 7 indicates the secondary wire thereof.

8 indicates a secondary circuit, one at each station, and 9 indicates areceiving-telephone in each of said secondary or receiving cir-- cellmay be replaced by any desired number of cells or by any other suitableunit of electric generation.

In the form of ourinvention shown in Fig. 1 the primary wire of theinduction-coil at each station is secured at one end to a post 16 and atthe other end to a plug 17. At station 1 are provided sockets 18, 19,and 20, insulated from each other and connected by wires 22, 23, and 24with the wires 14 and 15 and one pole of the battery, the other pole ofthe battery being connected to the linewire 2. The transmitting-circuitcan be made complete by inserting in any one of said sockets the plug17. At station 4 are provided the sockets 25, 26, and 27, adapted toreceive therein the plug 17, attached to one end of the primary wire ofthe induction-coil at that station. The primary wire of eachinductioncoil in this form of our invention is preferably a coiledspring-wire, which when extended or contracted presents more or lesscoils in proximity to the stationary windings of the secondary wire ofthe induction -coil. When the primary wire is drawn out, less coils arein proximity to the secondary wire, and the inductive efliciency betweenthe primary and secondary wires becomes decreased. By inserting plug 17at station 1 in the socket 18 only the battery unit or cell 11 will bein the circuit. If the plug is inserted in socket 19, two units or cells11 and 12 will be cut into the circuit. If the plug is inserted insocket 20, all the units will be cut into the transmitting-circuit. Inoperating this form of our invention the primary wire at station 1 iswithdrawn with the plug 17 to a point where the disturbing effects areno longer perceptible in the receiving-telephone 9 at that station. Theplug will then have been inserted in the socket, which will cut into thetransmitting-circuitthe number of battery units required to compensatefor the loss of efliciency due, to moving the wire 6 relative to thesecondary wire 7. The operator at station 4 operates his primary wireand plug 17 in a like manner by placing the plug 17 in the propersocket. When the disturbance on the transmitting-circuit decreases involume, the primary wires at each station may be contracted and theinductive efficiency thus increased and at the same time decreas-' ingthe strength of the telephonic currents by cutting out proportionatelycertain of the battery units.

In the form of our invention shown in Fig. 2 the Wires of theinduction-coils are stationary, and the primary wire of each coil isdivided into sections by leading therefrom at intervals wires 28, 29,and 30, which are also connected, respectively, with the members 31, 32,and 33 ofa series of sockets composed of the said members and themembers insulated therefrom 34, 35, and 36. The members 34, 35, and 36at station 1 are connected, respectively, to the wires 22, 23, and 24,which are respectively connected to the battery-cells 11, 12, and 13, asshown in Fig. 1. The line-wire 3 is connected at one end with theprimary wire of the induction-coil at station 4. The transmitters 10,secondary wires 7, and telephone-receivers 9 are disposed as alreadydescribed. Plugs 17 are provided to complete the transmitting-circuitthrough the proper sockets. In operating this form of our invention theinductive efficiency is varied by inserting the plugs 17 in differentsockets, thus cutting in or out of the transmittingcircuit portions ofthe primary wires 6.' With the plugs 17, as shown in this figure, in thesockets composed of members 32 and 35 the circuit will be completedbetween the line- Wire 2 and the primary of the induction-coil by thewires 29, 38, and 23, the plugs 17, and the socket members 32 and 35,the battery being connected, as already described when referring toFig. 1. In this position of the plugs 17 that portion of the primarywire of each induction-coil which is connected to the member 33 will becut out of the primary circuit, thus cutting out also from the inductiveaction that portion of the secondary wire 7 adjacent to such cut-outportion of the primary. The secondary wire at each station will thus beacted upon only by that portion of the primary wire of each coil locatedbetween the Wire 29 and the wire 3. In this condition of thetransmitting-circuit the batteries 11 and 12 are cut into the primarycircuit. It now the plugs 17 be inserted between the members 31 and 34at each station, thecircuit will I field, while but one battery unit orcell would be cut into the transmitting-circuit. The inductiveefficiency between the primary and secondary wires is thus varied byvarying the positions of the plugs 17 with reference to the sockets andthe strength of the telephonic circuits is oppositely varied thereby.

In the form shown in Fig. 3 the inductive efficiency between thetransmitting and receiving circuits is varied by cutting in or outportions of the secondary wire of each induction-coil from the secondarycircuit in which it is located. The different sections of the secondarywire of each induction'coil are connected by the wires 40, 41, and 42with the socket members 31, 32, and 33, respectively. The oppositesocket members 34, 35, and 36 are connected with the secondary circuit 8at each station by the wires 43, 44, and 45, respectively. One end ofthe secondary wire 7 is connected to the wire 42 and the other end tothe circuit-wire 8. By varying the position of the plug 17 at eachstation with relation to the socket members diiferent portions of thesecondary circuit will be thrown in or out of the inductive action ofthe primary circuit, thus varying the inductive efficiency be tween theprimary and secondary circuits. The telephonic currents traversing theprimary circuit may be then varied by any suitable means. 7 In the formof our invention illustrated in Fig. 4 the inductive efficiency betweenthe transmitting and secondary circuits is varied by varying the actionof a magnetic reinforcing agent 46. The core 46 is provided with ahandle 47, having a contact-flange 48, adapted to make and complete thecircuit through any one of a series of contacts 49, 50, 51, and 52. Thedifierent battery-cells are connected as already described, one polebeing connected to the line-wire 2, to which the contact 49 is alsoconnected. The contact 52 is connected to the other pole of the battery,and the contacts 50 and 51 are connected, respectively, to the wires 14and 15. One end of the primary winding is connected to the line-wire andthe other to the handle 47,.which with the flange 48 forms part of theprimary circuit. By drawing out the core 46 the flange 48 will makecontact successively with the contacts 50, 51, and 52, thus cutting in,respectively, one, two, or three units or cells. As it is Withdrawn thereinforcing influence on the primary and secondary windings of theinduction-coil will become decreased, while the battery-power is beingincreased, and moving it in the opposite direction will have an oppositeeffect. Thus the inductive efficiency between the transmitting andreceiving circuits will be varied simultaneously with the variation ofthe strength of the telephonic currents.

In operating the different forms of our invention the inductiveefficiency between the transmitting and the secondary circuits isreduced until the disturbing effects of the stray currents areeliminated from the receiving circuits and the strength of thetelephonic currents is correspondingly increased. As the disturbancedecreases the inductive efficiency is increased, thus permitting areduction in the strength of the battery required for telephonicpurposes.

It is not essential to the operation of our invention that the variationof the current be accomplished simultaneously with the variation of theinductive efficiency between the circuits. In the drawings We have shownin the battery single cells; but each of these cells can be duplicatedor increased to suit the occasion. In operating our invention theoperator at one station controls the strength of the current. Thevariation inefficiency at each station is controlled by the operator atthat particular station.

Other modifications than those shown and described may be made withoutdeparting from the spirit of our invention.

Having thus described our invention, what we claim,.and desire to secureby Letters Patent, is-

1. A telephone system comprising a primary electrical circuit, asecondary electrical circuit operated by induction therefrom, atelephone-receiver in the secondary circuit, means for causingtelephonic currents to traverse the said primary circuit, and means forvarying the inductive efficiency between the primary and secondarycircuits, substantially as described.

2. A telephone system comprising a primary electrical circuit, aplurality of secondary electrical circuits operated by inductiontherefrom, a telephone-receiver in each of said secondary circuits,means for causing telephonic currents to traverse said primary circuit,and means for varying the inductive efficiency between the primary andsaid secondary circuits, substantially as described.

3. A telephone system comprising a primary electrical circuit, asecondary electrical circuit operated by induction therefrom, atelephone-receiver in the said secondary circuit, means for varying theinductive efliciency between the said primary and the said secondarycircuits, means for causing telephonic currents to traverse the saidprimary circuit, and means for varying the strength of the telephoniccurrents traversing the primary circuit, substantially as described.

4. A telephone system comprising a primary electrical circuit, aplurality of secondary electrical circuits operated by inductiontherefrom, a telephonereceiver ineach of said secondary circuits, meansfor causingtelephonic currents to traverse the said primary circuit,means for varying the strength of the said currents, and means forvarying the inductive efficiency between the primary and the saidsecondary circuits, substantially as described.

5. A telephone system comprising a .primary electrical circuit, asecondary electrical circuit operated by induction therefrom,atelephone-receiver in the said secondary circuit, means for causingtelephonic currents to traverse the primary circuit, means for varyingthe inductive efficiency between the two circuits, and means forcorrespondingly but oppositely varying the strength of the telephoniccurrents in the primary circuit, substantially as described.

6. A telephone system comprising a primary electrical circuit, aplurality of secondary circuits operated by induction therefrom, atelephone-receiver in each of said secondary circuits, means for causingtelephonic currents to traverse .the primary circuit, means for varyingthe inductive elficiency between the primary and the secondarycircuits,'and means for correspondingly but oppositely varying thestrength of the telephonic currents in the primary circuit,substantially as described.

7. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse the saidcircuit, a secondary circuit, a telephone receiver in said secondarycircuit, an induction device comprising two elements inductively relatedto each other, one of said elements being located in the said primarycircuit and the other of said elements being located in the saidsecondary circuit, and means for varying the inductive efficiencybetween the two said elements,substantially as described.

8. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse the saidcircuit, a secondary circuit, a telephone-receiver in said secondarycircuit, an induction-coil comprising a primary and a secondary wire,the primary wire being .located in the said primary circuit and thesecondary Wire being located in the secondary circuit, and means forvarying the inductive efficiency between the primary and secondary wiresof the ind notion-coil, substantially as described.

9. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse saidcircuit, a plurality of secondary circuits, a telephone-receiver in eachof said secondary circuits, an induction-coil for each of said secondarycircuits, the primary wires of said induction-coils being located in thesaid primary circuit and the secondary wires thereof being locatedrespectively in the secondary circuits, and means for varying theinductive eiiiciency between the said primary wires and the secondarywires of the respective induction-coils, substantially as described.

10. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse the saidcircuit, a secondary circuit,.a telephonereceiver in said secondarycircuit, an induction device comprising two elements inductva /xii ivelyrelated to each other, one of said ele ments being located in theprimary circuit and the other of said elements being located in thesecondary circuit, means for varying, by increase or decrease, theinductive efficiency between the said two elements, and means forcorrespondingly but oppositely varying the strength ofthetelephoniceurrents traversing the primary circuit, substantially asdescribed.

11. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse the saidcircuit, a plurality of secondary circuits, a telephone-receiver in eachof said secondary circuits, a plurality of induction devices comprisingeach two elements inductively related to each other, one element beinglocated in the primary circuit and the other element being located inone of said secondary circuits respectively, means for varying, byincrease or decrease, the inductive efficiency between the respectiveelements of the said induction devices, and means for correspondinglybut oppositely varying the strength of the telephone-currents traversingthe primary circuit, substantially as described.

12. In a telephone system, the combination with a primary electricalcircuit, of means for causing telephonic currents to traverse the saidcircuit, a secondary circuit, atelephon'ereceiver in said circuit, aninduction-coil having a primary and a secondary wire, the primary wirebeing located in the primary circuit, and the secondary wire beinglocated in said secondary circuit, meansfor varying the inductiveefficiency between the said primary and secondary wires of theinductioncoil,

and means for oppositely varying the strength of the telephonic currentstraversing the said primary circuit, substantially as described. 13. Ina telephone system, the combination with a'primary electrical circuit,of means for causingtelephonic currents to traverse the said circuit, aplurality of secondary circuits, a telephone-receiver in each of saidsecondary circuits, a plurality of induction-coils the primary wires ofwhich are located in the said primary circuit and the secondary wires ofwhich are located one in each of said secondary circuits respectively,means for varying the inductive efficiency, by increase or decrease,between the primary and secondary wires of each of said induction-coils,and means for oppositely varying the strength of the telephonic currentstraversing the said primary circuit, substantially as described.

14. A telephone system comprising a transmitting-circuit, areceiving-circuit a portion of which is inductively related to a portionnot the transmitting-circuit, means for varying the extent of thatportion of one circuit which is inductively related to the othercircuit, and means for causing telephonic currents to traverse thetransmitting-circuit, I

substantially as described.

15. Atelephone system comprising a trans- IIO mitting-circuit, areceiving-circuit a portion of which is inductively related to a portionof the transmitting-circnit, means for varying, by increase or decrease,the extent of that portion of one circuit which is inductively relatedto the other circuit, means-for causing telephonic currents to traversethe transmitting-current, and means for varying the strength of suchcurrents, substantially as described.

16. A telephone system comprising a transmitting-circuit, a secondarycircuit, means for causing telephonic currents to traverse thetransmitting-circuit, an induction-coil provided with primary andsecondary Windings, one of which is disposed in the transmitting and onein the receiving circuits, and means for cutting in or cutting outportions of one of said windings from its circuit, substantially asdescribed.

17. A telephone system comprising atransmitting'circuit, means forcausing telephonic currents to traverse the said circuit, a secondarycircuit, an induction-coil having its primary wire disposed in thetransmittingcircuit and its secondary wire in the secondary circuit, andmeans for cutting in or cutting out from the transmitting-circuit portions of the primary wire of said inductioncoil, substantially asdescribed.

18. A telephone system comprising a transmitting-circuit, means forcausing telephonic currents to traverse the said circuit, a pluality ofsecondary circuits, a plurality of induction coils each having itsprimary Wire disposed in the transmitting-circuit and the secondarywires disposed respectively one in each of said secondary circuits, andmeans for cutting in or cutting out from the primary or transmittingcircuit portions of the primary wires of saidinduction-coils,substantially as described.

In testimony whereof We have signed our names to this specificationinpresence of two subscribing witnesses.

WILLIAM GONDON.

ALBERT BARRETT.

\Vitnesses:

WARREN D. I-IoUsE, G. W. DUVALL.

